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C program to find LCM of two numbers

Posted on December 18, 2023 By thecodepathshala No Comments on C program to find LCM of two numbers

Example

Input

Input number1: 12
Input number2: 30

Output

LCM = 60

LCM is a smallest positive integer that exactly divides two or more numbers. For Example

LCM (Least Common Multiple)
/**
 * C program to find LCM of any two numbers
 */

#include <stdio.h>

int main()
{
    int i, num1, num2, max, lcm=1;

    /* Input two numbers from user */
    printf("Enter any two numbers to find LCM: ");
    scanf("%d%d", &num1, &num2);

    /* Find maximum between num1 and num2 */
    max = (num1 > num2) ? num1 : num2;

    /* First multiple to be checked */
    i = max;
    
    /* Run loop indefinitely till LCM is found */
    while(1)
    {
        if(i%num1==0 && i%num2==0)
        {
            /*
             * If 'i' divides both 'num1' and 'num2'
             * then 'i' is the LCM.
             */
            lcm = i;

            /* Terminate the loop after LCM is found */
            break;
        }

        /*
         * If LCM is not found then generate next 
         * multiple of max between both numbers
         */
        i += max;
    }

    printf("LCM of %d and %d = %d", num1, num2, lcm);

    return 0;
}

/*
Output :

Enter any two numbers to find LCM: 12
30
LCM of 12 and 30 = 60
*/
C Programming, Programming Tags:C Programming, loop, loops

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